Vitamin D Deficiency in Patients With Hypertension

This study will assess whether aliskiren will lower clinic blood pressure and 24-hour blood
pressure in patients with hypertension and vitamin D deficiency. Additionally, this study
will further explore the potential additional effects of adding vitamin D to aliskiren in
this patient population.

Inclusion Criteria:

- Men or women over 21 years of age with a history of Stage 1 or 2 hypertension (defined
as a seated diastolic BP ≥ 90 mmHg and < 110 mmHg in the untreated state).

- Patients under treatment for hypertension must be willing and able to discontinue any
previous antihypertensive medications for the duration of the study.

- 25-hydroxyvitamin D levels < 30 ng/ml and > 12 ng/ml.

- Women of childbearing potential must be using a medically acceptable form of birth
control for the duration of the trial, must have a negative serum pregnancy test at
screening, and must have a negative urine pregnancy test within 7 days before
initiating aliskiren therapy.

Exclusion Criteria:

- Vitamin D levels < 12 ng/ml

- Known hypersensitivity or allergy to aliskiren

- Clinic blood pressure > 180/110 mmHg

- Known forms of secondary hypertension

- Chronic atrial fibrillation

- Uncontrolled or unstable cardiovascular diseases

- Shift or night workers

- Mid-arm circumference > 42 cm in diameter

- Current or recent (<1 year) alcohol or drug abuse

- Pregnant or lactating women